Method for forming zinc sheets



Dec. 6, .1938. c. WASSON v METHOD FOR FORMING ZINC SHEETS Filed April' 28, 1957 F W MI W W m W fitter/rays Patented Dec. 6, 1938 UNITED STATES PATENT OFFICE 2,139,215 METHOD FOR FORMING ZINC SHEETS Clinton I. Wasson, Muncie, Ind.

Application April 28, 1937, Serial No. 139,381v

2 Claims.

This invention relates to a process for preparing and forming zinc in sheets in a continuous operation from the molten zinc to the finished sheet thickness.

As indicated, the primary object of the invention is to provide a method which may be con-- tinuqus in operation rather than following the heretofore practice of molding billets and then passing these billets back and forth between rolls. A further feature of the invention is the maintaining of the correct temperatures in the zinc before and after being reduced in thickness.

These and other objects of the invention will become apparent to those skilled in the art in the following description of the invention which is illustrated more or less diagrammatically in the accompanying drawing, in which Fig. 1 is a vertical longitudinal section through apparatus used in performing the invention;

Fig. 2, a detail in transverse section on the lin 2-2 in Fig. 1; and

Fig. 3,'a similar detail of a modified form.

Like characters of reference indicate like parts in the two views in the drawing.

I provide-a quantity of molten zinc ill in any suitable tank ll, from which the zinc may be drawn at will such as by lifting a gate l2 by a handle l3 to permit the zinc to flow out a spout ii. A drum I5 is revolubly mounted by means of a center shaft l6 whereby the drum l5 may be revolved by any suitable means (not here shown).

Back of the drum I5 is positioned a fixed plate ll having a curvature, the radius of which slightly exceeds that of the outer face of the drum l5; Theplate I1 is spaced from the face of the drum ii a distance which determines the thickness of the sheet of zinc before it reaches the initial set of rolls as will be further described. The plate i1 is preferably provided with a cooling chamber l8 immediately therebehind.

The discharge end of the spout I4 is positioned to cause the molten zinc III to flow into a hopper l 9, the underside of which discharges into a space between the plate I1 and the periphery of the 45 drum IS. The zinc ID is flowed into the hopper is to maintain a sufiicient head on the molten zlncas will carry the zinc into the forming space between the drum l5 and plate ll. r

The drum I5 is continuously revolved in the direction of the down flowing zinc, counter-clock wise in the particular instance, so that as the molten zinc strikes the drum i5 and solidifies between it 'and the plate II, the zinc then becomes a sheet which is "carried on down around under 5 the drum it to be stripped therefrom by a stripper 20 so as to direct the sheet 2| on to a table 22. A seal is provided at each end of the drum between it and the plate l'l so as to define the width of the sheet 2i. In the particular form herein shown, Fig. 2, the drum is provided with an annular flange at each end extending from the drum to the plate I! sufficiently close so as to prevent leakage of the zinc when it first drops into the space between the drum and the plate.

In order to insure movement of the sheet 2| in 10 the space between the drum and plate, the drum may be provided with one or more roughened areas such as is indicated by the teeth 23, Fig. 2. These teeth receive the molten zinc therearound so that when the zinc solidifies, the sheet is then gripped firmly by the drum to insure travel of'the sheet therewith. The drum i5 is'preferably hollow so that ,a cooling fluid such as water may be introduced through the shaft I6 for the purpose of cooling the zinc contacting face of the drum as may be required. Likewise the chamber it may receive a cooling. fluid to circulate therethrough for the purpose of controlling the temperature of the plate I! and solidifying the zinc as desired.

The sheet of zinc 2| is carrledacross the table 22 to pass between the customary set of rolls 24, 25, to reduce the thickness of the sheet. In order to control the temperature of the sheet, a temperature control .tunnel 26 is provided immedi- 30 ately ahead of the rolls 24, 25, to have the sheet 2| pass therethrough. Depending upon the temperatureof the sheet 2! as it leaves the drum ii, the interior of the tunnel 26 may be either heated or cooled as may be required to control the temperature of the zinc in passing through the rolls. This condition in the tunnel 26 may be produced by introducing either gas or oil through the pipe 21 to burn inside the tunnel or air or water to cool the zinc by flowing thereagainst.

Successive passing through reducing rollers is t provided by carrying the sheet 2i continuously through as many consecutive rolls as may be desired to produce the final thicknessof the sheet. As'indicated by the drawing, a second tunnel 2Q is provided immediately ahead of a second set of rolls 29, 30. In'any event there should be a temperature control means at each set of rolls. As may be readily appreciated by those versed in the art, the working temperature rangeof zinc is narrow and must be controlled very effectively to produce an acceptable sheet. When the molten Zinc II) is first poured into the hopper |9,'it may be necessary to heat that hopper to prevent solidifying of the zinc therein until the hopper has been brought up to a temperature sufliciently high to prevent solidifying, by continuous flow of the zinc therethrough as would be the case after the process has been once set in operation. This heating of the hopper is may be produced by any suitable means such as by a gas jet flowing from a pipe 31 to have the flame play about the hopper.

From the foregoing description it will be apparent that a continuous formation of a finished zinc strip is produced in a manner greatly reducing the cost of forming sheets and also in a manner which will form a sheet of any desirable length. It is to be understood, of course, that the initial cast sheet may be varied somewhat in thickness by relative shifting of the plate l1 and the drum i5, one in respect to the other.

While I have described the invention above as referring to a sheet, I include within the meaning of "sheet narrow strips or bars. That is, the width of the sheet or strip is not limited but may be made any desired dimension and the cross sectional area may likewise be varied. Where a plurality of strips are required, the outer face of the drum l5 may be provided with a number of partitions 32, Fig. 3, so that these strips or bars are separately molded and carried between the form and shaping rolls thereafter.

While I have herein shown and described my invention in the form that is now best known to me, it is possible to employ variations without departing from the spirit of the invention and I therefore do not desire to be limited thereto beyond the limitations as may be imposed by the following claims.

I claim: I

1. That method of forming zinc strips in continuous lengths, which consists oi flowing molten zinc into an arcuate strip forming mold, pulling the solidified zinc from the bottom or the mold to induce molten zinc to follow into the mold thereafter, straightening the zinc strip as it leaves the mold into substantially straight line travel, conducting the zinc strip through horizontal molds removed from the arcuate forming mold and having a controlled temperature independent 01 the temperature of said arcuate mold and conformable with that of the metal crystalline structure of the zinc to prevent severance of the strip.

2. That method of forming zinc strips in continuous lengths, which consists of flowing molten zinc into an arcuate strip forming mold, pulling the solidified zinc from the bottom of the mold to induce molten zinc to follow into the mold thereafter, straightening the zinc strip as it leaves the mold into substantially straight line travel, con ducting the zinc strip through horizontal molds removed from the arcuate forming mold and having a controlled temperature independent of the temperature of said arcuate mold and conformable with that of the metal crystalline structure of the zinc to prevent severance oi the strip, said maintenance of temperature being obtained by passing the continuous strip through heat controlled tunnels adjacent said forming means.

CLINTON I. WASSON. 

